The diagram shows a stage micrometer whose divisions are $0.1\,\text{mm}$ apart, as seen through a microscope fitted with a graticule. What is the area of the microscope’s field of view at this magnification? $(\pi = 3.14)$
- A$\pi \times 12.5 \times 12.5 = 4.9 \times 10^2\,\mu\text{m}^2$
- B$\pi \times 50 \times 50 = 7.9 \times 10^3\,\mu\text{m}^2$
- C$\pi \times 125 \times 125 = 4.9 \times 10^4\,\mu\text{m}^2$
- D$\pi \times 250 \times 250 = 2.0 \times 10^5\,\mu\text{m}^2$